UPDATE: On November 25, 2019, the Food and Drug Administration (FDA) published a revised consumer update regarding safety concerns about cannabidiol (CBD) products. Due to limited research data, the FDA is unable to declare CBD products safe, according to the updated statement. The FDA warns that CBD can cause liver damage, increased drowsiness, and a number of other side effects. The impact of daily CBD use over a sustained period of time is unknown. Likewise, the FDA says there is insufficient research on the effect of CBD on the developing brain, on fetuses, and on the male reproductive system. The FDA has approved only one CBD product, which treats two rare forms of epilepsy. In late November, it issued warning letters to 15 companies for illegally selling products containing CBD.
These days, it’s tough to find an online community or social media group not singing the praises of cannabidiol (CBD) oil. This helps to explain why so many people are exploring its benefits for diseases and disorders ranging from Alzheimer’s and Parkinsons to PTSD and, yes, attention deficit disorder (ADHD or ADD). Though research suggests that CBD oil may benefit patients with epilepsy and other disorders, any such claims around ADHD are only that: claims.
What Is CBD? Does It Help ADHD?
CBD is a product of the marijuana (cannabis) plant with the high-inducing THC (tetrahydrocannabinol) compound removed, which means it is not psychoactive. CBD — often in the form of an oil, a tincture, or an edible — has been rumored to reduce anxiety, a common symptom among those diagnosed with ADHD symptoms. No one, though — not even the drug’s most hardcore advocates — claims CBD is a treatment for ADHD.
According to Mitch Earleywine, professor of psychology at SUNY-Albany and an advisory-board member of the National Organization for the Reform of Marijuana Laws (NORML), there is “no published data, let alone randomized clinical trials, [that] support the use of CBD for ADHD.”
Even so, word of CBD’s potential benefits — proven or otherwise — are often enough to compel some patients with ADHD to experiment. Dr. John Mitchell of the Duke University ADHD Program says that one of his patients, an adult woman with ADHD, tried CBD. Twice. On her own. Without his approval or supervision.
“I bought one vial for $50 that contained 30 gel tablets, and I took all of them over a few weeks,” says Mitchell’s patient, who preferred to remain anonymous. “I’d never tried CBD or any type of cannabis before, and I felt no changes. But I didn’t have any adverse effects, either.”
[Read This Next: Natural Remedies for ADHD: Treatment Without Medication]
Anecdotally, this outcome appears common for half of those trying CBD on their own — regardless of the quantity, quality, or type used. The other half claim some positives with regard to CBD and ADHD: “I was able to relax” or “I felt less manic” are common refrains. The problem, as Dr. Mitchell and the broader community of ADHD and CBD researchers point out, is a dearth of studies around CBD. No single research team has yet studied the possible effects — good or bad — of CBD oil for ADHD symptoms specifically.
“There are anecdotes that CBD may help with ADHD,” says Dr. Robert Carson, an assistant professor of neurology and pediatrics at Vanderbilt University who co-authored a 2018 study on the efficacy of CBD on epilepsy, “but this is true for many other symptoms or diseases. Thus, there may be patients whose ADHD symptoms improve after adding CBD, but we cannot generalize that anecdote more broadly. Secondly, the cases we’re most likely to hear about are the one where somebody had a great response — not the 10 who did not.”
“I am not aware of any scientific or clinical data that would speak to the safety or efficacy of using CBD in the treatment of ADHD,” says Ryan Vandrey, Ph.D., a member of John Hopkins University School of Medicine’s Behavioral Pharmacology Research Unit. “There is no scientific basis from which CBD should be recommended for use as a treatment for ADHD, nor is there any data that could speak to which product or dose would be appropriate.”
Is CBD Legal? Is It Safe?
To date, 33 states and the District of Columbia have passed laws broadly legalizing marijuana in some form; 10 other states and Washington, D.C., have adopted laws legalizing marijuana for recreational use. Even so, the U.S. Drug Enforcement Administration considers CBD, like all cannabinoids, a schedule 1 drug — making it as illegal as heroin and ecstasy. Despite this, one cannabis industry expert predicts that CBD products alone will comprise a nearly $3 billion market by 2021.
[Download This Guide for Free: The Best Supplements for ADHD Symptoms]
With all that profit on the horizon, why so few studies? At least partially to blame is the legality of CBD; it’s difficult to attain a federal grant to study a federally illegal drug. Politics also come into play, as do lingering public perceptions of cannabis as a gateway drug that may lead to schizophrenia, lethargy, or both.
Nevertheless, Dr. Mitchell feels that “The perception that [CBD] can have a negative effect has gone down because it’s becoming more available.”
This is not a perception shared by all of Dr. Mitchell’s peers, who note professional resentment and stigma regarding funding for cannabis research. “There’s a lot of political opposition coming from the business and scientific communities,” asserts Dr. Jacob Vigil, director of the University of New Mexico’s Medical Cannabis Research Fund. “It’s still highly stigmatized, and we need more studies.”
The studies done on CBD and ADHD to date amount to… practically nothing. One 2011 study showed that, among a group of 24 people with social anxiety disorder, the half who’d taken CBD were able to speak in front of a large audience. In 2015, researchers in Germany examined the relationship between cannabis (CBD and THC) and ADD in 30 patients, all of whom said they experienced better sleep, better concentration, and reduced impulsivity while using the cannabis products. Finally, a 2017 study looking at CBD oil and ADHD in adults found that the oil improved some symptoms, but that more studies were needed to confirm its findings.
The Dangers of Experimenting with CBD for ADHD
The Netherlands’ self-professed “cannabis myth buster,” Arno Hazekamp stated in a recent paper, “While new CBD products keep entering the market virtually unchecked, effective regulatory control of these products has stayed far behind. As a result, unknown risks about long-term effects remain unaddressed, especially in vulnerable groups such as children.”
“During [a person’s] development, I worry about cannabinoids, both CBD and THC,” says UCLA’s Evans. “There are adenosine receptors (and CB2 receptors) on the microglia that are critical for brain development, and CBD inhibits adenosine uptake. This may be a beneficial factor for epilepsy and autoimmune and inflammatory diseases, but who knows for ADHD.”
And while CBD may potentially benefit some patients with ADHD, “One is doing an experiment on oneself by taking CBD for ADHD,” Evans adds. “CBD is anti-inflammatory and I’m not sure there is good evidence mechanistically that for ADHD it might be helpful.”
It’s also unknown how CBD may interact with other medications. “CBD in any form is a drug, and thus has a potential for side effects or interactions with other drugs, specifically those metabolized through the liver [CBD is metabolized by the same enzyme in the liver that metabolizes many other medicines and supplements],” Carson says. “And with other ADHD medications that have sedating qualities, such as guanfacine or clonidine, there may be additive effects that may not be beneficial.”
Also potentially harmful is the non-standard and wildly fluctuating amount of CBD in most CBD products, even those labeled as “pure CBD oil.” Some such products may also contain other ingredients — pesticides, additives, herbs, and even THC. “CBD alone has multiple actions on the cells in the brain and we don’t know which ones are clearly responsible for its known benefits,” Carson says. “It gets more complicated when we have less purified products that also include THC and CBDV [cannabidivarin].”
Dangers may also exist in the method of delivery. CBD is packaged and consumed in oils, tinctures, or edibles — each one absorbed differently by a person’s body. “The labeling in this industry,” says Vigil of UNM, “is horrific.”
‘Natural’ Doesn’t Necessarily Mean ‘Safe’
Once CBD enters the body, no one yet knows how it works. Its long-term effects are a mystery. Exactly how does CBD work — in the brain and over many years? As Dr. Carson bluntly puts it: “We don’t know and we don’t know.”
None of this will stop some people from self-medicating with CBD or trying it on their children. “Apparently there are products offering about 30mg of CBD per dose,” Earleywine says. “I rarely see published work with humans that shows much of an effect below 300mg, which… would get quite expensive… So it’s probably a waste of time and money.”
“The bottom line,” Evans says, “is that there is a dearth of research on all cannabinoid actions — because of its schedule 1 classification — and no clear scientific evidence I can find to endorse or not endorse CBD use for ADHD.”
Perhaps because researchers have documented no negative links between CBD and ADHD, some “patients go through trial and error with CBD,” Vigil says. “First they go on the Internet, where they start with an isolate CBD. Then they try the vanilla products — only to find they get more benefits when they add THC.
“They do that because cannabis is so variable that patients are forced to experiment. Also because clinical trials can’t really tell you anything about the decisions that patients actually make in the real world. And finally because there’s not going to be a uniform solution for everybody.”
“Families need to think very hard about potential risks versus benefits for treating other disorders, including ADHD,” Carson advises. “So please discuss what you are thinking about doing with your child’s physician. In the absence of good data, a dose of 1 milligram per kilogram of body weight per day is where most patients start when using CBD for epilepsy — and this seems to be well tolerated. But if the side effects from any medication are worse than the problem was to begin with, that patient might be on too much.
“I like to remind families,” Carson adds, “that just because something is natural does not mean it is safe.”
[Expand Your Knowledge: Why Sugar is Kryptonite for ADHD Brains]
Updated on December 16, 2019